Exadata X3 is a hardware revision, not software. So perhaps the better question to ask would be: are there any user-affecting feature changes in Exadata storage server software 11.2.3.2 (which was released concurrently with X3 hardware)?

The major new feature of this release was the introduction of the write-back flash cache. I'm not aware of any user-affecting changes to smart scans, storage indexes, or columnar compression. Major changes like this would probably require changes to the database software as well.

Correction to these two points - these are not X3 features. A rack of X2 hardware that is upgraded to the latest Exadata software version (currently 11.2.3.2.1) would also have these features. They are not hardware features at all, as Marc mentioned earlier in this thread.

Major changes like this would probably require changes to the database software as well

I was wondering about this. Since the Exadata Storage Servers run their own software, I thought that there might be (or can possibly be) changes here independent of changes in the database server software.

Major changes like this would probably require changes to the database software as well

I was wondering about this. Since the Exadata Storage Servers run their own software, I thought that there might be (or can possibly be) changes here independent of changes in the database server software.

And changes like the write-back flash cache are great examples of changes that are implemented in the storage server without the database even known about it. But features like smart scans and hybrid columnar compression require the involvement of the database layer, and with no recent database releases, this might be a reason why we didn't seen this type of change in 11.2.3.2.

While the writeback flashcache feature was introduced in a storage server release, it does require 11.2.0.3 BP9 (August 2012) to be used at the database layer. It's very important to try to keep the software stacks matched up from a release date standpoint. You never know what strange things may come up if you don't ever patch your database homes and apply the latest patches to the storage servers.

Hi Dan,
you answer is not the whole picture , Just upgrading the storage software version does not enable writeback caching by default. you need to drop the flash cache , change the caching mode and recreate the flash cache. We just saw an instance where the engineers did the update and forgot to make the writeback change so the flash cache is still running as write through.

Agreed - I should have worded my response more clearly. I meant to say that the software upgrade makes those features available, even on X2. However, enabling/employing those features may (and as you note, does) require some additional steps.